package com.issc.helper;

import com.issc.util.CollectionUtil;
import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.MapListHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.sql.Connection;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * 数据库操作助手类
 */
public final class DatabaseHelper {
    private static final Logger LOGGER= LoggerFactory.getLogger(DatabaseHelper.class);
    private static final QueryRunner QUERY_RUNNER;
    private static final BasicDataSource DATA_SOURCE;

    private static final ThreadLocal<Connection> CONNECTION_HOLDER;
    private static final String DRIVER;
    private static final String URL;
    private static final String USERNAME;
    private static final String PASSWORD;

    static {
        CONNECTION_HOLDER=new ThreadLocal<>();
        QUERY_RUNNER=new QueryRunner();

        DRIVER=ConfigHelper.getJdbcDriver();
        URL=ConfigHelper.getJdbcUrl();
        USERNAME=ConfigHelper.getJdbcUserName();
        PASSWORD=ConfigHelper.getJdbcPassword();

        DATA_SOURCE=new BasicDataSource();
        DATA_SOURCE.setDriverClassName(DRIVER);
        DATA_SOURCE.setUrl(URL);
        DATA_SOURCE.setUsername(USERNAME);
        DATA_SOURCE.setPassword(PASSWORD);
        DATA_SOURCE.setDefaultAutoCommit(false);
        try {
            Class.forName(DRIVER);
        } catch (ClassNotFoundException e) {
            LOGGER.error("can not load jdbc driver",e);
        }
    }

    /**
     * 获取数据库连接
     */
    public static Connection getConnection(){
        Connection conn=CONNECTION_HOLDER.get();
        if(conn==null) {
            try {
                conn = DATA_SOURCE.getConnection();
            } catch (SQLException e) {
                LOGGER.error("get connection failure", e);
                throw new RuntimeException(e);
            } finally {
                CONNECTION_HOLDER.set(conn);
            }
        }
        return conn;
    }
    /**
     * 关闭数据库
     */
    public static void closeConnection(){
        Connection conn=CONNECTION_HOLDER.get();
        if (conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                LOGGER.error("close connection failure",e);
                throw new RuntimeException(e);
            }finally {
                CONNECTION_HOLDER.remove();
            }
        }
    }
    /**
     * 查询实体列表
     */
    public static <T>List<T> queryEntityList(Class<T> entityClass,String sql,Object...params){
        List<T> entityList;
        try {
            Connection conn=getConnection();
            entityList=QUERY_RUNNER.query(conn,sql,new BeanListHandler<T>(entityClass),params);
        } catch (SQLException e) {
            LOGGER.error("query entity list failure",e);
            throw new RuntimeException(e);
        }finally {
            closeConnection();;
        }
        return entityList;
    }
    /**
     * 查询实体
     */
    public static <T> T queryEntity(Class<T> entityClass,String sql,Object...params){
        T entity=null;
        try {
            Connection conn=getConnection();
            entity=QUERY_RUNNER.query(conn,sql,new BeanHandler<T>(entityClass),params);
        }catch (SQLException e){
            LOGGER.error("query entity failure",e);
        }finally {
            closeConnection();
        }
        return entity;
    }
    /**
     * 执行查询语句
     */
    public static List<Map<String,Object>> executeQuery(String sql,Object...params){
        List<Map<String,Object>> result;
        try {
            Connection conn=getConnection();
            result=QUERY_RUNNER.query(conn,sql,new MapListHandler(),params);
        } catch (SQLException e) {
            LOGGER.error("execute query failure ",e);
            throw new RuntimeException(e);
        }
        return result;
    }
    /**
     * 执行更新语句(包括update\insert\delete)
     */
    public static int executeUpdate(String sql,Object...params){
        int rows=0;
        try {
            Connection conn=getConnection();
            rows=QUERY_RUNNER.update(conn,sql,params);
        } catch (SQLException e) {
            LOGGER.error("execute update failure",e);
            throw new RuntimeException(e);
        }finally {
            closeConnection();
        }
        return rows;
    }
    public static <T> boolean insertEntity(Class<T> entityClass,Map<String,Object> fieldMap){
        if (CollectionUtil.isEmpty(fieldMap)){
            LOGGER.error("can not insert entity:feildMap is empty");
            return false;
        }
        String sql=" INSERT INTO "+getTableName(entityClass);
        StringBuilder columns=new StringBuilder("(");
        StringBuilder values=new StringBuilder(")");
        for (String feildName:fieldMap.keySet()){
            columns.append(feildName).append(", ");
            values.append("?, ");
        }
        columns.replace(columns.lastIndexOf(","),columns.length(),")");
        values.replace(values.lastIndexOf(","),values.length(),")");
        sql+=columns+" VALUES "+values;

        Object[] params=fieldMap.values().toArray();
        return executeUpdate(sql,params)==1;
    }
    /**
     * 更新实体
     */
    public static <T> boolean updateEntity(Class<T> entityClass ,long id,Map<String,Object> fieldMap){
        if (CollectionUtil.isEmpty(fieldMap)){
            LOGGER.error("can not insert entity:feildMap is empty");
            return false;
        }
        String sql="UPDATE "+getTableName(entityClass)+" SET ";
        StringBuilder colums=new StringBuilder();
        for (String feildName:fieldMap.keySet()){
            colums.append(feildName).append("=?, ");
        }
        sql+=colums.substring(0,colums.lastIndexOf(", "))+" WHERE id=?";
        List<Object> paramList=new ArrayList<>();
        paramList.addAll(fieldMap.values());
        paramList.add(id);
        Object[] params=paramList.toArray();
        return executeUpdate(sql,params)==1;
    }
    /**
     * 删除实体类
     */
    public static <T> boolean deleteEntity(Class<T> entityClass,long id){
        String sql="DELETE FROM "+getTableName(entityClass)+" WHERE id=?";
        return executeUpdate(sql,id)==1;
    }

    private static <T> String getTableName(Class<T> entityClass) {
        return entityClass.getSimpleName();
    }

    /**
     * 开启事务
     */
    public static void beginTransaction(){
        Connection conn=getConnection();
        if (conn!=null){
            try {
                conn.setAutoCommit(false);
            } catch (SQLException e) {
                LOGGER.error("begin transaction failure",e);
                throw new RuntimeException(e);
            }finally {
                CONNECTION_HOLDER.set(conn);
            }
        }
    }
    /**
     * 提交事务
     */
    public static void commitTransaction(){
        Connection conn=getConnection();
        if (conn!=null){
            try {
                conn.commit();
            } catch (SQLException e) {
                LOGGER.error("commit transaction failure",e);
                throw new RuntimeException(e);
            }
        }
    }
    /**
     * 回滚事务
     */
    public static void rollbackTransaction(){
        Connection conn=getConnection();
        if (conn!=null){
            try {
                conn.rollback();
                conn.close();
            } catch (SQLException e) {
                LOGGER.error("rollback transaction failure",e);
                throw new RuntimeException(e);
            }finally {
                CONNECTION_HOLDER.remove();
            }
        }
    }
}
